1. Field of the Invention
The present invention relates to an electronic control apparatus and a data rewriting system.
2. Description of Related Art
In the related art, a technology is known that enables a control program or control data that is stored in a rewritable non-volatile memory such as a flash memory or EEPROM (Electrically Erasable and Programmable Read Only Memory) which are embedded in an electronic control apparatus for controlling a vehicle, to be rewritten by using a dedicated rewriting apparatus after shipping the electronic control apparatus to the market.
In Japanese Unexamined Patent Application Publication No. 2004-310221, a technology is disclosed in which ID (Identification) information for identifying all microcomputers is stored in advance in a non-volatile memory embedded in a representative microcomputer of a plurality of microcomputers installed in an electronic control apparatus, and this representative microcomputer transmits the ID information of a microcomputer that is a target of which data is rewritten, to an external tool in accordance with a request from the external tool (memory rewriting apparatus).
The external tool recognizes the microcomputer that is the target of rewriting based on the ID information received from the electronic control apparatus, adds the ID information of the microcomputer to rewriting data, and transmits the rewriting data to the electronic control apparatus. Each of the microcomputers in the electronic control apparatus performs rewriting of a control program or control data that is stored in the non-volatile memory, by using the rewriting data with the ID information directed to each of the microcomputers.